1. Field of the Invention
The present invention pertains to packages for dispensing an elongated, flexible member such as a probe or catheter, and in particular to an improved dispensing system for a pacing lead.
2. Description of the Prior Art
Because catheters, and the probes associated with them, have an intended use which requires their insertion into a patient, it is critical to optimal performance to deliver the probe from a sterile package to the patient in a manner which limits exposure of the probe to the outside atmosphere. Typically, the catheter has been packaged separately, with the insertion of the associated probe following the insertion of the catheter into the patient. The insertion of the elongated flexible probe into the catheter should be smooth, to minimize installation time, with the inserting probe providing negligible resistance to the user, and with the probe emerging from a package of relative simplicity.
However, efforts to provide a dispensing apparatus for a probe meeting the criteria set forth above have resulted in dispensing systems which include notable constructional complexities. For example, a known system incorporates a reel rotatably mounted on a base in a sterile package. The probe is wound onto the reel for storage with the reel rotating to deliver the probe from the reel when the probe is removed from the package. The reel introduces an undesirable mechanical complexity to the package. Moreover, as the probe is removed from the reel, the probe is capable of binding to prevent withdrawal of the probe from the package. Moreover, failure of this rotating mechanical device could undesirably contribute to the failure of the insertion of the probe into the catheter, thus compromising the sterility of both the catheter and the probe.
Another type of serpentine tubing and surgical cord retractors is disclosed in U.S. Pat. No. 4,174,816 which shows a surgical cord and tube retractor, wherein one end of the cord or tube is secured within a housing, the other end being accessible at a side of the housing, enabling the cord or tube to be withdrawn. The cord or tube passes over a plurality of fixed and longitudinally moving rotating pulleys. As the cord or tube is drawn from the enclosure, the movable pulleys are lifted toward the fixed pulleys, developing a force that tends to pull the cord or tube back into the enclosure. It is desirable to eliminate mechanical complexities from a dispensing system for a pacing lead, and to provide that the pacing lead is not wound around any rotatable object, to be retracted back into the packaging tray upon release by the operator.
Alternative constructions of dispensing packages which eliminated the mechanical reel have been attempted. For example, a dispensing tray having a spiral track for disposing the pacing lead thereon has been attempted. However, in such a configuration, withdrawing the lead from the tray caused the lead to tighten against the wall of the spiral track, to bind up in the tray instead of sliding out of the tray, making insertion of the lead into the catheter difficult.
An alternative configuration proposed locking respective loop ends to locking tabs provided on the walls of a storage compartment for the lead. Such a configuration would result in additional design complexities as well as introducing a requirement of a snap release of the lead from the locking tabs, thus putting additional forces on the pacing lead as it is inserted into the catheter as well as to undesirably affect the smoothness of the delivery of the pacing lead to the catheter.
Another packaging device is shown in U.S. Pat. No. 4,126,221, which describes a package for multiple strands of surgical sutures. Each strand is separately wound in a coil comprising a series of convolutions, each convolution being laterally displaced from adjacent convolutions and placed in sequence within the package. To form the convolutions, each suture is wound in a figure-8 pattern over two dowels, which are then withdrawn. Adjacent sutures are also wound in the figure-8 pattern, and the coils are placed side-by-side in the package with one end of each suture extending to a dispensing orifice from which it can be readily drawn out. As an end of a suture is pulled from the package, the figure-8 pattern collapses or unwinds, permitting the suture to be withdrawn without tangling. However, a packaging concept useful for multiple sutures may not be suitable to prevent entanglement of successive loops of a single elongated pacing lead of considerable flexibility. For example, suture materials can easily be retained in place without the need to provide intervening barriers to maintain the desired configuration and position for the suture. Such a construction is clearly not suitable to position a springy flexible probe of a length substantially longer than the package which is to store the probe.